This invention relates to a suspension system and more particularly to an improved control arrangement for a vehicle suspension system wherein the suspension travel of two of the wheels is interrelated to each other.
U.S. Pat. No. 5,486,018 issued Jan. 23, 1996, shows a suspension system for vehicles wherein individual shock absorbing arrangements located at each wheel control the damping of that wheel. Pairs or more of these shock absorbers are, however, interrelated by means of an accumulator and flow control arrangement so as to provide an increase in the stiffness of the suspension system to control such things as pitch and/or roll.
This system utilizes a pair of accumulators, preferably formed by concentric portions of a floating piston assembly, that experience equal displacement when the same direction of loading and the same magnitude is applied to the two interrelated wheels. However, if one damping unit moves in one direction, and the other moves in the other, as is caused by either roll in the case of interconnected side units, or pitch, in the case of interconnected front and rear units, then the damping stiffens and these roll and/or pitch conditions can be controlled. A damping arrangement is provided for controlling the flow between the two chambers externally of the individual interconnected shock absorbers under this condition. This damping arrangement comes into effect when there tends to be unequal or opposite directions of fluid displacement.
Although the devices shown in that patent are quite effective, many of them embody relatively complicated structures that require the accumulator housing to be formed in principal part from a main casting. This adds considerably to the weight and cost of the system. In addition, the structures shown require considerable machining to accommodate the various piston and piston areas.
It is, therefore, a principal object of this invention to provide an improved accumulator and flow control arrangement of this general type.
It is a further object of this invention to provide an improved accumulator and flow control system for a vehicle suspension system that is relatively low in cost and light in weight.
Many of the embodiments disclosed in the aforenoted patent also have only fixed orifices that control the interrelation between the two suspension units. It is, however, desirable to be able to fine tune the system upon installation in the vehicle.
It is, therefore, a still further object of this invention to provide an improved accumulator and flow control device of this general type that embodies a simple yet easily yet externally adjusted damping arrangement.